Model.create(Array) promise is spreading arguments

[jtmarmon]

@vkarpov15 mentions in #2478 that if you pass an array to Model.create, the promise is resolved with an array. However, [in the docs](http://mongoosejs.com/docs/api.html#model_Model.create it looks like the arguments are spread, and my code is showing the same. Would love some clarification here if possible

[vkarpov15]

3.8.x always returns them as a spread, 3.9.x (and 4.0) will return them as an array if you pass an array and spread if you pass in a spread. The reasoning for this is that it's a backwards breaking change, so needs to be in the unstable branch. 4.0 is currently waiting on MongoDB server 2.8 and MongoDB node driver 2.0 to stabilize before releasing.

[jtmarmon]

got it. thanks

[Soviut]

I created an issue about this regarding the callback as well #2602

[jtmarmon]

oy this came back and bit me again. For anyone who stumbles upon this, Q and Mongoose basically have opposing philosophies (until 3.9/4.0). if you convert Model.create(<array>) to a Q promise, you'll lose all results past index 0. see kriskowal/q#357

[vkarpov15]

Yeah Q doesn't support resolving with a spread, but mongoose's underlying library mpromise does. Technically, neither promises/A+ spec nor ES6 spec explicitly prohibits resolving with a spread, although ES6 implies only a single value. To work around this, in 3.9.x and upcoming 4.x, Model.create() will return a spread if you passed it a spread and an array if you passed it an array.

[jtmarmon]

Actually what just occurred to me is that I could use Q.spread. Still confusing though. Gonna be excited to get arrays back in 4.0